package com.hmdp.utils;


import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
public class RedisIdWorker {

    //开始时间戳
    private static final long BEGIN_TIMESTAMP=1640995200L;
    //序列号位数
    private static final int COUNT_BITS=32;

    private StringRedisTemplate stringRedisTemplate;

    public RedisIdWorker(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }

    public long nextId(String keyPrefix){
        //生成时间戳
        LocalDateTime now = LocalDateTime.now();
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);
        long timestamp = nowSecond - BEGIN_TIMESTAMP;

        //生成序列号
        String date = now.format(DateTimeFormatter.ofPattern("yyyyMMdd"));
        long count = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + date);
        //拼接并返回

        return timestamp<<COUNT_BITS|count;
    }

//    public static void main(String[] args) {
//        LocalDateTime time = LocalDateTime.of(2023, 5, 1, 0, 0, 0);
//        long second = time.toEpochSecond(ZoneOffset.UTC);
//        System.out.println(second);
//    }
}
